Induction means



l www Dec. 26, 1961 3,014,470

G. BURRELL INDUCTION MEANS Filed Nov. 2, 1956 5 Sheets-Sheet l Dec. 26, 1961 G. BURRELL 3,014,470

INDUCTION MEANS Filed Nov. 2, 1956 3 Sheets-Sheet 2 IN V EN TOR.

ATTORNEY Dec. 26, 1961 G. BURRELL INDUCTION MEANS Filed Nov. 2, 1956 3 Sheets-Sheet 3 IW/1 "IW-NNUU I /l//l/lvllll l l 11111 i y 2? ,11111111 i y f7 if i l l if y y @d i Zfgggfg United States Patent spiano lNnUo'rroN MEANS Gilbert Burrell, Lansing, Mich., assigner to General Motors Corporation, Detroit, lt/lich., a corporation of Dela- Filed Nov. 2, 19st, ser. No. 620,024 2 Claims. (Cl. 12s- 52) The present invention relates to internal combustion engines and more particularly to the induction systems therefor.

in order to obtain the maximum power and performance from an internal combustion engine, it is essential that each of the cylinders receives a charge la maximum volume and that each of the charges be substantially identical bot'n as to their proportions `and volumes. One means for accomplishing this is to employ an intake manifold having a plurality of carburetors adapted to work in unison or sequence. Although there are numerous induction systems for accomplishing thisy :objective they are not entirely satisfactory. It has been found that where several carburetors are employed and particularly where they are compounded to be actuated in sequence, a uniform distribution of the charge is not btained during all operating conditions.` Accordingly, it is necessary to make compromises in such installations to obtin satisfactory operation at all times.

yIt is therefore proposed to provide an induction system which is adapted to insure satisfactory charging of the engine cylinders during all operating conditions. More particularly, this is to be `accomplished by providing an induction system employing an intake manifold having a plurality of carburetor risers arranged to receive primary and secondary carburetors. A primary carbuetor riser is. disposed in the center of the manifold to be substantially uniformly spaced from all of the cylinders and adapted to supply a charge to all of the cylinders at all times.`

Secondary carburetor risers which receive carburetors aadpted to operate during only certain conditions are symmetrically located about the primaiy carburetor riser and adjacent the opposite ends of the manifold. This permits each secondary carburetor to'charge a group of cylinders that are equally spaced therearo-und. As a result the primary carburetor will be substantially uniformly spaced from all the cylinders and each of the second-ary carburetors are evenly disposed. between the cylinders in the group it charges.

In the three sheets of the drawings:

FIGURE l is a plan view of an intake manifold embodying the present invention and having portions thereof 'broken away.

FIGURE 2 is a side View of the manifold in FIGURE 1.

FIGURE 3 is a transverse cross-sectional View taken substantially along the plane of line 3--3 in- FIGURE l.

FIGURE 4 is a longitudinal cross-sectional View taken substantially along the plane of line 4 4 in FIGURE 1.

FIGURE 5 is a longitudinal cross-sectional view taken substantially along the plane of line 5-5 in FIGURE l.

FIGURE 6 is a transverse cross-sectional view taken substantially along the plane of line 6 6 in FIGURE l.

Referring to the drawings in `more detail, the present invention may be embodied in an intake manifold 10 which is particularly adapted to be employed on a V-type engine 12. The present engine includes a cylinder block forming a pair of angularly disposed lbanks of Aaligned cylinders and an upwardly opening space 14 therebetween. In the present instance each bank of cylinders includes a pair of center cylinders and a pair of end cylinders. A cylinder head 16 is secured to each bank yto close the upper ends of the cylinders and form combustion chambers, each of which is charged by a separate intake passage that extends transversely through the head. The outer Patented Dec. 26, 1961 rie charging the hot exhaust gases into exhaust manifolds.

The present intake manifold l@ is a single integral casting, the opposite sides 20 and 22 of which are machined to iitkagainst the faces 18 on the inner sides of the Vcylinder heads 16. The manifold 10 may be secured in this position over the space 14 by bolts or any other suitable means. The forward end o-f the manifold 10 may include a transverse cooling header 24 that collects the liquid in the cooling system and discharges it through an outlet 26 for return to the radiator.

The center of the manifold 16 has a primary carburetor riser 28 on the top thereof which includes a mounting Iflange Sii adapted to receive a primary carburetor 32. This -riser 28 includes a pair of substantially vertical riser or charge supply passages 34 and 36, the upper ends of which form openings 3d and Litladapted to communicate with charge forming passages in the carburetor 32 and receive `a combustible mixture of air and fuel therefrom.

A pair of substantially horizontal distributionpassages 42 and i4 extend longitudinally of the manifold ilu substantially parallel to each other and pass directly under the riser 28. As a result the riser passages 34 and 36 intersect the tops of the distribution passages 42 and 44 adjacent the centers thereof. It may thus be seen that the charges from the pair of charge forming passages in the carburetor will flow directly into the distribution passages 42 and 44 and toward the opposite ends thereof.

' A pair of transverse branch passages 46, 48, 50 and 52 are provided adjacent each end of the manifold 1t); Each of these branch passages 46, 48, 5@ and 52 extend Substantially transversely of the manifold 10 to form separate ports 54, 56, S8, 60, 62, 64, 66 and 63 in the sides 2t) and 22 thereof positioned to register with the intake ports in the cylinder heads 16. The center of each branch passage 46 to 52, inclusive, communicates with an end of one of the distribution passages 42 or 44. It may thus be seen that there are two pairs of branch passages for each distribution passage so that the charge of air and fuel in each distribution passage may ii'ow through two branch passages `and into four cylinders.

`Since the branch passages 46 to 52, inclusive, extend completely across the manifold 1t), each of the passages will communicate directly with a pair of intake ports and will thus charge a pair of cylinders. To insure optimum charging of the cylinders it is desirable 4to prevent the charging operation for one cylinder interfering with the charging of 'another cylinder, i.e., there should be a minimum amount of overlapping of the intake strokes of the pair of cylinders interconnected by a common branch passage. Therefore, in Vaddition to employing separate distribution passages and -groups of branch passages, each branch passage may interconnect the intake port for an end cylinder in one bank with an intake port for `a center cylinder in the opposite bank. If this arrangement is employed the branch passages in each pair will Abe crossed. Thus the centers of the branch passages 46 are disposed at the same elevations as the distribution passages so that the center of one passage may pass over the center of the other passage.

It may thus be seen that during normal operation a combustible charge of air and fuel will be formed in the primary carburetor 32 and will iiow downwardly through the riser passages 34 and 36 and into the centers of the distribution passages 42 and 44. The charge will then flow towards the ends of the distribution passages and into the branch passages for distribution into the cylinders. Since the passages to the various cylinders are all substantially identical, they will all receive substantially identical charges. Normally, this charge will be adequate; however, during some conditions it may be desirable to supplement the charge from the primary carburetor 32. Accordingly, a pair of secondary carburetor risers 70 and 72 may be provided on the opposite ends of the manifold 10. Each of these risers 7i) and 72 includes a mounting flange 74 and 76 adapted to receive a secondary carburetor 78 and 80 and a pair of Vertical riser passages 82 and S3 that form a pair of openings 84 and 86 that are adapted to communicate with the mixture forming passages in the secondary carburetors 78 and 80. The riser passages 82 and 83 extend downwardly from the flange 74 or 76 with one riser passage 82 in each riser communicating with the intersection of the upper distribution passage 42 and its branch passages and the other riser passage 83 communicating with the intersection of the other distribution passage 44 and its branch passages. It will be seen that the riser passages are capable of delivering a charge into the branch passages adajcent to the inlet ports and at substantially equal distances therefrom. The secondary carburetors may be actuated by any suitable means. For example, they may be controlled by means similar to those disclosed and claimed in copending application S.N. 626,099, Carbureting System, invented by Gilbert Burrell and tiled November 2, 1956, now Patent No. 2,886,021, issued May l2, 1959.

When an engine is operating at subnormal temperatures the particles of fuel tend to settle out of the charge and prevent proper operation of the engine. Accordingly, during such periods it is desirable to heat the surfaces of the induction passages and the charge flowing therethrough. A heat box 87 may be formed around the primary riser 28 and the junction of the primary riser passages 34 and 36 and the distribution passages 42 and 44. IIn order to supply the heat for this box exhaust ducts 8S may extend laterally therefrom. This duct 88 is adapted to communicate with the exhaust passages in the cylinder heads `16. The box 87 should be arranged to apply the heat to only that portion of the manifold 10 where the fuel precipitates, i.e., the area immediately below the riser passages 34 and 36. To improve the heat transfer to the charge, heat absorbing fins 90 may project into the exhaust gases. It is also desirable to provide slight depressions 92 in the floors of the distribution passages 42 and 44 so that any liquid fuel will collect therein and be re-evaporated by the application of heat thereto before it passes into the cylinders. It should be noted that it is desirable to confine the application of heat to the area around the primary riser and to eliminate heating the area around the secondary risers. Thus during full power operation the charge will not be heated to thereby limit the amount of power. It may thus be seen that an intake manifold has been provided in which a plurality of carburetors .are provided to operate in sequence while still insuring a uniform distribution of the charge during all operating conditions. In addition, the charge without heating the charge during full load operation.

It is to be understood that, although the invention has been described with specific reference to a particular embodiment thereof, it is not to be so limited since changes and alterations therein may be made which are within the full intended scope of this invention las defined by the appended claims.

I claim:

l. An intake manifold having a V-type internal combustion engine having a pair of axially disposed banks of cylinders, said manifold comprising first and second distribution passages extending longitudinally of said manifold and adapted to respectively communicate with only one-half the number of engine cylinders, a first pair of branch passages having centers respectively communicating with the opposite ends of said first distribution passage and extending transversely thereof, a second pair of branch passages having centers respectively communieating with the opposite ends of said second distribution passage and extending transversely thereof, each of said branch passages being adapted to communicate with a portion of the number of cylinders communicating with the associated distribution passages, a primary carburetor river havng vertical charge supplying passages communicating with the centers of the first and second distribution passages, and secondary carburetor risers at the vopposite ends of said manifold having vertical charge References Cited in the file of this patent UNITED STATES PATENTS Sullivan .Tune 6, 1939 Caris et al. Nov` 27, 1956 UNITED STATES PATENT. OEEICE`V CERTIFICATE 0E CORRECTION Patent No SqOlllATQ December 26 l9l Gilbertl Burrell It is hereby certified that error appears in the above numbered patent requiring correction and that the said Let'lzersy Patent should read es corrected below.

Column 1 line 27 for "obtain" read obtain Column 3 line 22 for "adejcent" read u adjacent, --3 column 4V line lOV after ''Cherge" first occurrerlce1 insert, emay be heated to insure proper mixing of the Charge g line ll7 for "river havngf* read riser having --o Signed and sealed this 8th day of May 1962,

' (SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents 

